The combination of coffee and cereal at breakfast may not be a good one, according to new research.
A research team working on the links between caffeine and type 2 diabetes has suggested that instead of choosing low-sugar cereals and coffee, some people may be far better off with a sweeter morning cereal and a decaffeinated drink.
The essential finding is that drinking coffee at breakfast can dramatically increase blood sugar levels. This is not thought to be a problem for people who live a generally healthy lifestyle, as their bodies can probably handle short-term increases in blood sugar. However, those who have a weight problem may find that it is their morning coffee which will give them a problem, not the sweetness of their cereal.
"Coffee is a very healthy beverage, as long as you have a healthy lifestyle in terms of exercise, diet and weight control," says professor Terry Graham of the University of Guelph, Canada, who has been working on the subject for 10 years. "However, those whose bodies already have trouble producing insulin should avoid caffeine with meals.
His study, reported in the American Journal of Clinical Nutrition, says that those who drank caffeinated coffee with a breakfast cereal recorded higher blood sugar levels, even when they chose a low-sugar cereal. Even drinking caffeinated coffee an hour before eating cereal can significantly affect the body's blood-sugar response, according to his research.
"If you have caffeinated coffee, the levels go higher than they would have if you didn't have the caffeinated coffee with that particular cereal," professor Graham told the Canadian media. âYou might get up, have your coffee and think, ‘well, I had better behave myself now and I'll have All-Bran'. In fact, the blood-sugar response to the All-Bran exceeded what our subjects showed if they had decaf and a moderately high-sugar cereal.
"So, combining what you might think of as a more optimal cereal with coffee, ends up giving you a response higher than you would have expected from the less-optimal cereal."
The researcher also added that he found a "marked impact" when those who drank caffeine at breakfast followed it with a carbohydrate-based lunch, because caffeine levels in the body would barely have decreased.
"In this case, the levels went quite high - you thought you dodged the bullet at breakfast, but it got you between the eyes at lunch."